The invention is generally related to latches, keepers and latch assemblies, and in particular to latches, keepers and latch assemblies for use with slidable partitions such as doors and gates.
Latch assemblies, or latches, are commonly used to engage movable partitions such as doors or gates with other structural members, e.g., posts, walls, or panels, or other doors or gates. One use of a latch, for example, is in connection with a slidable partition such as a sliding gate.
A predominant use of a slidable partition is in selectively providing access to an enclosed or secured area. To this extent, oftentimes a lock is used in connection with a latch on a slidable partition to prevent the slidable partition from being opened by an unauthorized party. However, many latch and lock designs are susceptible to tampering, which may enable an unauthorized party to defeat a latch and/or lock to gain entry through the slidable partition.
For example, a number of sliding gate designs engage with a structural member (e.g., a fixed post or other partition) using a locking mechanism that operates a latch member to engage with a cooperative keeper on the structural member. The latch member typically projects outwardly from an end surface of the sliding gate in the direction of movement of the sliding gate. The locking mechanism is capable of moving the latch member between an unlocked position, where the latch member does not engage with the keeper, and a locked position, where the latch member engages with the keeper to prevent the sliding gate from disengaging from the structural member. Moreover, oftentimes the latch member is spring-loaded such that, when the locking mechanism is locked, but the sliding gate has not yet been moved to its closed position, the latch member deflects from its locked position to its unlocked position as the sliding gate is closed, and then springs back to the locked position once the sliding gate is moved to the fully closed position. Opening of the sliding gate requires actuation of the locking mechanism to move the latch member from the locked to the unlocked position.
While a spring-loaded latch member simplifies the operation of a sliding gate, such a latch member also often facilitates tampering by unauthorized parties. Specifically, oftentimes it is possible to access the latch member even when the sliding gate is closed, possibly permitting the latch member to be manually deflected to its unlocked position independent of the locking mechanism. For this reason, a significant amount of effort has been expended in the area of protecting a spring-loaded latch member from unauthorized tampering.
Conventional designs typically incorporate various guards to prevent external access to a spring-loaded latch, typically including cooperative members having opposing recesses and projections that serve to restrict external access to one or more sides of a latch. A number of designs do not, however, restrict access to all sides of a latch, and thus present a relatively greater security risk. Other designs that do restrict access to all sides of a latch are typically constructed of somewhat complicated interlocking members, which are more difficult and costly to manufacture. Further, in some designs the interlocking members may still provide gaps that an enterprising party may be able to exploit to gain unauthorized access through the gate. Moreover, many conventional designs are difficult to install or retrofit on existing structures.
One design that has overcome many of this drawbacks is disclosed in U.S. Pat. No. 6,196,034, which is assigned to the same assignee as the present invention, and which is incorporated by reference herein. In this design, a latch assembly incorporates a pair of overlapping tubular guard projections that are respectively secured to a pair of opposing structural members. The tubular designs of the projections define an enclosed area that is effectively isolated from all sides. As such, a latch member that projects through the enclosed area within the overlapping projections is substantially protected from unauthorized tampering.
In the aforementioned design, one of the overlapping tubular guard projections is typically secured to the end surface of one of the structural members, while the other projection is secured to a base plate of a keeper secured to the end surface of the other structural member. Each projection extends generally in the direction of the engagement axis along which the slidable partition slides, and both the end surface of the structural member, and the base plate oppose one another and extend perpendicular to the engagement axis.
The keeper also includes a transverse plate joined along an edge of the base plate and extending perpendicular to the base plate, running generally along a side face of the structural member. In addition, a mounting plate is joined to an opposite edge of the transverse plate from the base plate and extends generally parallel to, but in an opposite direction from, the base plate. When installed, the mounting plate overlies the end surface of the structural member to orient the base plate in a generally perpendicular relationship to the engagement axis.
Typically, the keeper is economical to construct, with the base, transverse and mounting plates being formed from a single piece of sheet metal bent along two parallel edges. In addition, the keeper is typically capable of being installed in either upright or inverted orientations, permitting the same keeper design to be used in both left- and right-handed installations, as well as in both inside and outside slider installations.
However, it has been found that, in an inside slider installation, the mounting plate of the keeper is accessible from the unsecured side of the enclosure when the slidable partition is in a closed position and secured via engagement of the latch assembly. As such, removable fasteners cannot be used to secure the mounting plate to the end surface of the structural member, otherwise an unauthorized person seeking to gain entrance through the slidable partition could simply remove the fasteners to disengage the keeper from the structural member.
Instead, non-removable, blind hole fasteners, such as Plusnut fasteners, are typically used to permanently secure the keeper to the structural member. Such fasteners, however, tend to be comparatively expensive and difficult to use. Furthermore, once installed, the keeper is no longer removable from the structural member, even by authorized service personnel.
Therefore, a significant need continues to exist for an improved mechanism for restricting access to a latch for a slidable partition such as a sliding gate, particularly for a mechanism that is less expensive and complicated than conventional designs.
The invention addresses these and other problems associated with the prior art by providing an apparatus, latch assembly, keeper and installation method for use in slidable partition applications in which the keeper is formed of first and second angle members that are secured together in an overlapping relationship to define a U-shaped channel within which is disposed a tubular guard projection for protecting a latch from tampering by unauthorized personnel.
In particular, a keeper consistent with the invention includes first and second angle members, and is configured to be secured to a structural member among a pair of structural members. One of the pair of structural members is disposed on a slidable partition and is configured to slide relative to the other structural member along an engagement axis. The first angle member includes first and second plates oriented generally perpendicular to one another, with the first plate configured for installation on one of the structural members to orient the second plate in a perpendicular relationship to the engagement axis. The second angle member includes third and fourth plates oriented generally perpendicular to one another, and the second angle member is configured to be secured to the first angle member with the second and third plates at least partially overlapping one another and the fourth plate extending generally parallel to the first plate to define a generally U-shaped channel between the first and second angle members. The keeper also includes a tubular guard projection secured to and extending from one of the second and third plates within the U-shaped channel and configured to extend along the engagement axis when the first plate is installed on the structural member.
Additionally, an apparatus and a latch assembly utilize an additional tubular guard projection that is configured to be secured to the end surface of the other structural member from that to which the keeper is secured. The additional tubular guard projection circumscribes a latch member receiving aperture defined in an end surface of the other structural member, and extends outwardly from the end surface and in a direction generally along the engagement axis. The tubular guard projections are also sized and configured relative to one another to overlap along the engagement axis when the structural members are secured to one another.
These and other advantages and features, which characterize the invention, are set forth in the claims annexed hereto and forming a further part hereof. However, for a better understanding of the invention, and of the advantages and objectives attained through its use, reference should be made to the Drawings, and to the accompanying descriptive matter, in which there is described exemplary embodiments of the invention. dr
FIG. 1 is an exploded fragmentary perspective view of an enclosure consistent with the invention, taken from an unsecured side of the enclosure, with portions of a latch assembly used therein cut away.
FIG. 2 is a perspective view of the fixed post and assembled keeper from FIG. 1, taken from the secured side of the enclosure.
FIG. 3 is a fragmentary side elevational view of the unsecured side of the enclosure of FIG. 1, showing the sliding gate thereof disposed in a closed position relative to the fixed post.
FIG. 4 is a cross-sectional view taken through lines 4xe2x80x944 of FIG. 3.
FIG. 5 is a cross-sectional view taken through lines 5xe2x80x945 of FIG. 3.
FIG. 6 is an exploded fragmentary perspective view of the keeper of FIG. 1, illustrating the incorporation of optional end caps therewith.
FIG. 7 is a top plan view of the keeper of FIG. 6, illustrating an end cap installed thereon.